Lubricating composition



Patented Mar. 11, 1947 2,417,088 ICE LUBRICATIN G COMPOSITION Carl F. Prutton, Cleveland Heights, Ohio, assignor, by mesne assignments, to The Lubri-Zol Development Corporation, Cleveland, Ohio, a corporation of Delaware No Drawing. Application February 17, 1942, Serial No. 431,259

8 Claims. 1

This invention relates, as indicated, to lubricants and more particularly to lubricating compositions and methods of lubricating having certain advantages over such compositions and methods now familiar to those skilled in the art.

This application is a continuation-in-part of my copending application Seria1 No. 247,000, filed December 21, 1938, which has now issued into Patent No. 2,276,341, which in turn is a continuation-in-part of copending application Serial No. 737,070, filed July 26, 1934, and copending application Serial No. 755,987, filed December 4, 1934.

7 At the present time there is an increasing demand for lubricating compositions capable of resisting the effects of extreme pressures and temperatures under conditions of use and it is an object of the present invention to provide such a composition.

By "extreme pressures, as referred to above, is meant pressures of or in excess of 10,000 pounds per square inch, such pressures being now commonly encountered in hypoid gears, bearings, contact surfaces of cylinders and piston rings in internal combustion engines, and many other points. Such pressures tend to cause the rupture of the continuous thick film of lubricant which separates bearing surfaces under more moderate conditions. A region of thin film lubrication results which is also sometimes described as "boundary lubrication.

A particular object of my invention is, therefore, to provide a lubricant and method of lubricating which will function to advantage under conditions of extreme pressure and effectively prevent seizure and scoring of the relatively moving metallic surfaces being lubricated.

Other objects of this invention will appear. as the description proceeds.

To the accomplishment of the foregoing and related ends, this invention, then, comprises the means hereinafter fully described and particularly pointed out in the claims. The following description sets forth in detail certain approved combinations of ingredients embodying my invention, such disclosed means constituting, however, but certain of the various forms in which the principle of the invention may be employed.

Broadly stated, this invehtion contemplates the use in lubricating'compositions of esters of naphthenic acids used either alone or preferably in combination with a separate halogenated organic compound.

When compositions are desired suitable for use in the lubrication of internal combustion engines, it is obvious that only relatively small proportions of these esters should be added to the hydrocarbon base oil. Since, however, it has been found that the presence of even small amounts of these esters will considerably enhance the 2 lubricating properties of mineral lubricating oils especially when employed in combination with separate halogen compounds. liquid compositions are satisfactory for many purposes and may contain as little as 0.1% of the ester although from about 1% to about 5% by weight, based on the amount of oil, is generally more desirable. Amounts up to 20% may be used for certain purposes. Concentrates which may be further blended with base stocks may contain up to as high as of these esters of naphthenic acids.

The base oil employed in the composition of this invention is generally mineral oil'but it is to be understood that any other suitable hydrocarbon lubricating oil, whether naturally occurring or synthetic," may be employed as the oil base.

The oil base of the preferred composition of this invention is a, highly refined mineral lubricating oil having a viscosity and other characteristics such as to make the same suitable for use as the crankcase lubricant for internal combustion engines. The highly refined mineral lubricating oils suitable for use as the base in the improved compositions of my invention may be conveniently classified in accordance with their viscosity index, three such classes being oils having a V. I. up to 30; oils having a V. I. from 30 to about and oils having a V. I. of above 70. Obviously the oil base selected may contain appropriate constituents in addition to plain mineral oil such as pour point depressors and the like, since these conventionally employed materials have been found entirely compatible with 'the addition agents which characterize the final blends comprising my invention.

It is also within the contemplation of this invention to provide'the addition agents in the form of a concentrate in a suitable oil, said oil containing rather high percentages of the addition agents. Such concentrates may be employed for future blending with a lubricating oil in the proportions desired for the particular conditions of use. i

The following list of esters suitable for use in accordance with the invention isintended to be illustrative only and it is to be understood that various other compounds coming within the group of esters of naphthenic acids broadly are included within the scope of the invention:

Esters of naphthenic acids:

(1) Aliphatic esters, e. g.,

Propyl diiso-propyl naphthenates Methyl naphthenate Ethyl naphthenate Buty1 naphthenates (n-, iso-, and sec-) Amyl naphthenates Lauryl naphthenate Cetyl naphthenate (2) Aromatic esters. e. g.,

Phenyi naphthenate t-Amyl-phenyl napnthenate Benzyl naphthenate Cresyl naphthenate Xenyi naphthenate (3) Cyelo-aiiphatic esters, e. g.,

Cyclopentyi naphthenate Cyclohexyi naphthenate v Methyl-cyclohexyi naphthenates Di-methyl-cyclohexyl naphthenates Tri-methyl-cyclohexyl naphthenates- Propyl-cyclohexyl naphthenates Amyl-cyclohexyl naphthenates Lauryl-cyclohexyl naphthenates Cetyl-cyclohexyl naphthenates Cyclohexyl-carbinol naphthenates cyclohexyl-cyclohexyl naphthenates Any esters may be used which are derived from naphthenie acids by cle, R, for the replacea substituting an organic radi Examples of R are the following:

I. Hydrocarbon rndieles:

(A) Aikyi A ral cies myl (n, iso, sec. and tertiary) Lauryl Ceti'l Carnauhyi M ontanlyl Xenyl Nannthyl (alphaand beta A nthracyl Phenanihryi (C) cxio-aikyltm iicles (D) Alkylate i aryl radieles Lauryl (E) Alkylaied yclnnen y] Cyeloheryl Cyrlohentyl Cyelohexyl-cyelohexyl Radix-ins formed by the as those listed above (13), with any of the radicles. e. 2., those listed above (A), the following:

Methyl Ethyl Propyl (n-. and iso-) Bntyl (n-. isoand see-l Specific examples (rcsyl El hylmhonyl Tctra-ethyiphenyl t-Amrl phenyl Lauryl-phenyl Cel yi-phenyl Ceryl'phen yl Meihyl-naphthyl Iso-nropyi-nanhthyl t-Amrl-naphl hyl Lauryl-nnnhthyl Cetyi-nnnhthyl lso-nropyl-xcnyl -xcn vl oycloalkyl radicles ble hydrogen of the acid.

alkylation of aryl 'radicles, such alkyl or with any oi oi alkyiated aryl radlcles are as follows:

Radleles formed by the alkylation olcyclohlkyl rariitlcl asi such as those listed above (C), with any of the radicles, such as those listed above.

Amyl

radicles, e. z.

radielea, o. g.

'(a Crclo-alkylated alkyi nail-m. e.

Nanhthcnyl Hexnhydmbenzyl Cyclohexyi-ethyl Oyelohexyl-amri Specific examples I. Hydrocarbon radiclea-Contlnued:

(I) Arylatcd eyelo-aik vl radlcies, e. g.

Phenyl-oyclnhexyl xenyl-cyclnhexyl Naphthybeyclohexyl II. Oxygen-containing organic radicles (A) Of the ether type, c. g.

Methoxy-phenyl thoxy-phenyl Lauroxy-phcnyi Cyclohexoxy-phenyl ienoxy-cyclohexyl Phenoxy-eth Phenoxy-lanryl Phenoxy-eetyl Amylhcnoxy-ethyl Phenv -ethoxy-etbyl (B) of the Stoaroyl-naphthonyl.

Naphi henoyl-phenyl Naphthenoyl-xonyl Naphthenoyl-naphthyl Naphthenoyl-amyl Naphthonoyl-lauryl N aphthenoyl-cetyl Naphthcnoyl-phenoxy-phenyl Naphthenoyl-cyclohexyi Phenoxybenzoyl-phenyl (C) Oi'the ester tyne.-i. e.

Derived from hydroxy-esters by the removal or the (2) Esters of polyhydroxy alcohols and phenols in which at least one bydroxyl group remains unsubstituted. tor example-esters [ended by esterlfying the following so that at least one hydroxyl group remains in the resulting ester:

Ethylene glycol I Dieth iene lycol Prop 'iene cols But one ulyoois Poiy-hydroxy benzenes i Dlhydroxy-benaeneo Resorclnol Cateebol Hydroqulnono Tri-hydroxybcnzeuea Pyrozollol QJIZOOO CIHII CcHu (B) O! the thlo-ketone t Thio-acetylhcny l 'lhldbenzoy -phenyl Thlo-stearoyl-phenyl Thio-naphthenoyl-phenfl Thio-stearoyl-cyclobexy (0) 0f the thio-ester type, e. g., of thio-carboxylio acids.

are:

derived from hydroxy-esters Examples of such radicles CHa-(EH-C-OR s l cm-cH-d-sa ll CHa-iJH-C-BR S ll -CH:-CH;SC-R

Where R is methyl, ethyl, butyi, amyl, lauryl,

steamy], naphthenyl. etc.

(D) Bedicles derived from hydroxy-organic poiysulphides by removal of the hydroxy group, e. g.

R- R am.

where R is hydrogen or an allryl or cyclo-alkyl group where R is an alkyl an alkyiene group.

or cycio-alkyl group and R is As previously indicated, this invention com-,

prises the use in lubricating compositions of esters of naphthenic acid. These esters, when used alone, that is, without any other addition agent effective to cooperate therewith, are admirably suited to impart to the lubricant to which they are added, properties such as oiliness, reduction in rate of wear which enables such lubricant to be used under conditions where the plain refined mineral lubricating oil base would be unsatisfactory for use alone.

These esters of naphthenic acid, which may be used alone, may be either the straight esters or such esters halogenated, and accordingly this invention comprises the use in lubricating compositions of both the halogenated and unhaloe genated esters of naphthenic acids. The specific examples previously given are the unhalogenated esters which may be thus used. Each of the esters thus identified, either generically, sub-generically or specifically, may be modified by halogenation, and the halogenated ester thus derived used as the addition agent.

It is believed unnecessary to repeat the foregoing list in the more specific identification of the halogen-bearing esters, since it will be obvious to those skilled in the art what the halogen counterparts of these esters would be. The usual halogenation process, well-known to those familiar with the art, may be employed in the preparation of the halogenated esters. The usual halogenatlon step may be followed by subsequent stabilization treatments, such as air blowing, alkali washing, or the like, in order that the halogen retained in the ester will be sufllclently stable, and. not too readily liberated during storage and use.

The following, however, is a list of specific examples of halogen-bearing esters of naphthenic acids which will be found particularly suitable and this, therefore, constitutes a preferred group of compounds for use in the lubricating compositions of my invention.

-Chlorinated methyl naphthenate containing about 20% chlorine Chlorinated butyl naphthenate containing about 10% chlorine Chlorinated methyl cyclohexyl naphthenate con,-

taining about 10% chlorine Chlorinated methyl-cyclohexyl naphthenate containing about 40% chlorine Chlorphenyl naphthenates Chlorbenzyl naphthenates Dichlorbenzyl naphthenates Dichlor-xenyl naphthenates Tet'ra-chlor-xenyl naphthenates 'I'etra-chlor-phenoxy-phenyl naphthenates Hexachlor-phenoxy-phenyl naphthenates This invention thus contemplates the utilization of halogen in combination with the esters of naphthenic acid. The halogen may be, as indicated above, included in the same molecule as by halogenation of the ester, itself, or the halogen may be present in a separate molecule, i. e. a separate halogen-bearing organic compound. It has been found that the esters of naphthenic acid have a cooperative effect when employed in conjunction with a separate halogenated organic compound. This is true whether the naphthenic acid ester be halogenated or unhalogenated. This cooperation between the naphthenic acid esters and the separate organic halogen compound is manifested by the ester cooperating with the separate halogen compound in activating the latter, so that a higher film strength may be attained from the use of a given amount of halogen in the form of the separate organic halogen compound, and moreover, extremely stable halogenated organic compounds, which would have a low degree of activity, may be rendered especially active by the incorporation therewith of an ester of naphthenic acid, whether the latter be halogenated or unhalogenated.

This invention, therefore, includes the combined use of theesters of naphthenic acids, either halogenated or unhalogenated, with a separate organic halogen compound, and this combination, for the reasons above given, is the preferred embodiment of my invention, since in such combination, the greatest utility of the esters of naphthenic acids may be realized.

For purposes of classification, the halogenated organic compounds, which thus comprise one component of the preferred embodiment of my invention, may be conveniently grouped as oxygen-free" and oxygen-bearing.

In the case of the halogenated aromatic oxygen-free compounds, it is preferable for certain uses that the halogen be attached to a carbon atom of the benzenoid ring. These latter compounds are sometimes more desirable because of their non-corrosive character and general stability.

The halogenated oxygen-free organic compounds as noted may be either:

A. Aliphatic, such as halogenated:

I. Hydrocarbons, notably, those containing from four to ten carbon atoms. e. 2.,

Chlorinated or iluorinatcd hexane Chlorinated or fluorinated octane Chlorinated or fluorinated decane ll. Amines. primary, secondary and tertiary, e. 3., hexylamines,

di-amylamines, tri-amylamines such as:

Chlorinated or fluorinated tri-amyl amine Chlorinated or fluorinated hexyl amines Also:

Chlorinated or fluorinated tributyi amine III. Nitriles Halogenated ethyl nitrile Halogenated butyi nitrile or (preferable for certain types of uses as noted above):

B. Cyclic compounds, such as halogenated:

i. Benzene and related compounds such as:

(l) Halogennted benzene, e. g.,

The dichlorhenzenes, notably the ortho compound Ortho-dihrom benzene The fluorinated benzenes (2) Haiogenated derivati es of benzene such as:

(a) Halngenated homologs of benzene, e. g.,

' Mono-chlor toluene Mono-chior xylene Mono-chior eymene Ethyl mono-chlor benzenes Propyi mono-chlor benzenes Di-ethyi mono-ehior benzenes Ethyl dichlor benzenes Propyl dichior benzenes Di-ethyl :lichlor benzenes Di-ethyl tetrachlor benzenes (b) Hniozenaied amino derivatives or benzene, e. 3.,

hlorinated aniline (preferably the ortho- Mono-chlnr aniline c. g... Chlorinated amino-diphenyis Chlorinated amino methyl diphenyls (c) Halogenated hydrodiphenyls, e. g

Chlorinated phenyl hexahydrobenzene I Chlorinated dodecahydrodiphenyl lIl. Na )hthalenc. such as {1) Chlorinated naphthalene, e. 3.,

a-Mono-chior naghthalene (2) Brominated napht aiencs, e. g.,

a-Monohrom na hthalene (3) Fluorinated napht alene (4) Haiogenated derivatives of naphthalene such as:

(a) Halogenated homologs of naphthalenes, e. 3.,

Chlorinated methyl naphthalene notably the alpha compound,- ch orinated propyl, and isopropyl substitution products of naphthalene (b) Halogenated amino derivatives of naphthalene,

e. g., Chlorinated naphthylamines Mono-chior a-naphthyi amino (4:) Haiogenated hydronaphthalenes, e. 3.,

Chlorinated docahydronaphthelene Cyclic compounds, such as halogenated-Continued:

IV. Pheggnthrene and anthrocene and related compounds. such (1) Chlorinated phenanthrene, chlorinated anthracene (2) Halogensted derivatives oi phenanthrene and anthracene. such as: (a) Haloizenatcd homologs Chlorinated l-methyl phenanthrene Chlorinated ll-methyi phenanthrene Chlorinated 9,10 dimethyi phenanthrene Chlorinated ropyl and isopropyl derivatives of phenant rene Chlorinated dimethyl anthracenes Chlorinated a-methyl anthraeene Chlorinated B-methyl anthracene Chlorinated propyi and isopropyl derivatives oi anthracene (b) Hniogenated amino derivatives, 0. 3.,

Chlorinated phenanthrylamines Chlorinated anthramines (c) Halogenated hydrophenanthrenes and halo ,genated hydroanthracencs, e. g., Chlorinated retene oil (contains hydro retene) V. Chrysene. picene, and related compounds, including their derivatives, such as homoiogs, amino derivatives and other substitution products. VI. Bridged ring compounds, such as the compounds, and their derivatives, e. g., pmenc. VII. Hctcrocyciic compounds, such as pyridine, quinoline pyrroie, thlophene, and derivatives of them, a. 3., mono chlor pyridine.

terpenes and related chlorinated Very satisfactory results may be obtained when two or more different halogens are present in the same molecule, orthobrom-chlor benzene, ethyl-bromchlorbenzenes, and the fiuorinated chlorine compounds being good examples of such compounds. If the aromatic compounds have been alkylated they are often especially effective.

'As a matter of convenience, the halogenated di-phenyls and substituted diphenyls, as well as halogenated substituted benzenes where two or more phenyl groups are directly linked, may be inclusively referred to as halogenated polyphenyls.

Some of the best examples of the aromatic compounds are:

Chlorinated benzene, 3-1. (1) e. g.,

Di-chlor benzene (notably the ortho compound) Mono-chlor toluene, 3-1. (2) (a) Oi-ethyl tetrachlor benzene Chlorinated diphenyl 3-11 (1) Chlorinated aniline B-1 (2) (b) Chlorinated pyridine B-VIII. Chlorinated quinoline B-VII.

Good. examples of halogenated aliphatic hydrocarbons are:

Fluorinated pentane Fluorinated hexane Fluorinated octane Fluorinated di-iso-butene Halogenated petroleum derivatives, particularly halogenated petroleum oils and waxes;

Halogenated oxygen bearing organic compounds I. Aliphatic, or carbon chain type.-Oxygen-bearing derivatives oi:

A. Hydrocarbons of the parailin series, B. Hydrocarbons of the oieilne series and C. Hydrocarbons oi the acetylene series.

II. Organic ring type.-Oxygen-bcaring derivatives oi:

A. Carbon ring" type compounds (a) Oi the aromatic. or allied type. including oxygen- -,bearing derivatives of benzene. naphthalene, anthraceiie, etc., also compounds oi the bridged ring type such as the terpcnes, and related compoun s.

() Of the ClilSS including the cycloparaifins, cyclooleiines, etc. Examples oi this class are oxygen-bearingderivatives oi the following:

(1) Hydrogenation products of benzene (e. g., cyclohexane, cyclohexene, cyclohexadien such as hydrogenated phenol, notably: cyclohcxanol di-hydrophenol, tetrahydro-phcno (2) Hydrogenation products oi naphthalene o. g., decahydronaphthalene, tetrahydronaphtlialcnc, etc):

such as the hydrogenated naphthols. (3) Naphthalcncs, such as naphthentc acid,

c. (C) Di mixed type such as derivatives oi indene,

hydrinene, hydranthracene, etc. B. He(te)rocycllc" type compounds Oi the aromatic or allied type including derivatives of pyridine, quinoline, etc. (b) Other types such as iuriural, iuran and its derivatives and derivatives of thiophenc, pyrrole, etc.

The oxygen-bearing derivatives of the foregoing compounds mayalso be classified according to the nature of the attachment of the oxygen to the molecule, viz.:

I. Directly attached to one or more carbon atoms, as in the case of:

i) Ethers and analo ous compounds (2) Compounds containing the radicle, such as alcohols and other derivatives of carl inol (including phenols, crcsols, naphthols, etc.) (3') Compounds containing the carbonyl Y I radicle, such as amides, aldehydes, ketones, organic acids, esters and salts oi organic acids, thio-acids and esters oi thi acids (4) Compounds in which oxygen iorms a part oi the ring structure, c. g. iuran and its derivatives. etc.

(5) Corn ounds with inorganic radicle where the oxygen lulphlte lulpninic acid uiphonc .uiphunic acid lulphoxide 1 Thio-sulphate The following table indicates some of the compounds which re particularly suitable for use in accordance with the'present invention:

A. Aromatic (1) Phcnols,'o.g.

ohlor henol Mmioch or a-naphthols 1 (2) Alcohols. c. 5.,

r-benzylalcohols The ch (3) Ketones; e.

Mono chlor benzophenones Cliior naphthyl kctones .Chlor-niethyl-henzophenones s. e. a.

- Chlorphenyl acetic acids *3; Chlor salicylic acids lor phenyl stcaric acids ty Dlniethylchlor ihthalates Di-ethyl chlorp ithalates Dihutylclilorphthalates Methyl chlor sailcylatcs Methyl chlor-phenyl-ntearates A. Aromatic-Continued:

(6) Ethers. e n.

Chlorinated diphenyl other Chlorphonyl ethyl cthcrs Chlorinated dixenyl ether Chlorinated dinnphthyl other Alkylatcd chlor-diphcnyl etliers (7) Non-aromatic oxygcmhcaring organic ring compounds:

Halogenatcd cyclohcxanol Halogenatcd esters of naphthenic acids (8) Oxygen-hearing hetcrocyclic compounds: (a) Halogenated furane and derivatives of iurane. e. g.

l-lalogenated esters of pyromucic acid (i'uroates) Halogenated iuriuryl alcohol and esters of it, e. 3.,

Cnlorinatcd iuriuryl acetate (b) Halogenaied otygcn-bcaring derivatives of thiophene and pyrrolc. e. g.

Chlorinated esters of thiophcne Carhoxylic acids and chlorinated Esters oi pyrrole carhoxylic acids 13. Chain compounds (1) Alcohols Fluorinatcd octyl alcohol Fluorii ated decyl alcohol Fluorinated lauryl alcohol Fluorinatod cetyl alcohol (2) Esters 1 Methyl dichlnrstearate Chlorinated lri-lauryl phosphate Chlorinated tri-ethyl phosphate (3) Ketoncs Chlorinated dlhutyl ketone Chlorinated di-amyl ketone It is, of course, to be understood that the above lists of compounds are intended merely to illustrate the type of compound suitable as one component of the addition agent of this invention and are not to be construed as limiting said component to th particular groups or examples there disclosed.

It is believed that under'conditions of extreme pressure the halogenated addition agents of this invention react chemically or physico-chemically with the metallic surfaces to form a non-fluxing surface which will not seize or score. This invention is not intended to be limited, however, by any particular theory or explanation of the action upon the metallic surfaces.

All of the various halogens are effective when employed in accordance with the present invention but chlorine is generally preferred inasmuch .as it is the least expensive and one of the most effective of the halogens. Bromine and fluorine are more expensive and the latter is relatively diflicult to handle but they are each usable in accordance with this invention. Iodine is not so readily obtainable as the other halogens and is quite expensive but it also is satisfactory in providing effective addition agents. Itshould also be noted that two or more different halogens may be present in the same molecule. The brom chlor and fiuorinated chlorine or bromine compounds give especially satisfactory results. When used in conjunction with a naphthenate, an amount of from about 0.1% to about 20% by weight, based on the amount of oil, of the separate halogen compound is all that is required to render the finished lubricant eflicient under conditions of extreme pressure. Seldom is there any need to employ more than 10% and usually about 3% of the halogenated addition agent will be found to be ample for most purposes.

Since, in general, the loss of the addition agent by volatilization will be less for compounds having a low volatility, the vapor pressure of the compounds should, for most purposes, be less than atmospheric pressure at temperatures up to C. It is usually desirable, especially for use in internal combustion engines, that the vapor pressure be less than atmospheric at temperatures up to C. In the case of compounds which are stable at temperatures up to their boiling points, this condition may be expressed by stating that the boiling point of the compound should, in general, be higher than 140 C., and-for certain uses,

improve the viscosity index or cold test of the lubricant and a lubricating composition according to this invention which also has a separate oilivness increasing agent has been found to be esp cially eflective.

As illustrative of specific embodiments of my invention I will list below a number of specific examples of final blends which, it will be noted, are divided into two groups, the first group being motor oils adapted for use in the crankcases of internal combustion engines, and the second group being gear oils useful, for example, in the gearcases of automobiles and the like.

1. Motor oils Per cent 1. Mineral 99.5

Chlorinated methyl naphthenate containing about 20% chlorine ,5 2. Mineral nil 99.5

Chlorinated methyl cyclohexyl naphthenate containing about chlorim .5 3. Mineral nil 99 Dichlorobenzyl naphthenate 1 4. Mineral nil 98.5 Ortho dichlorbenzene 1.0 Methyl naphthenate .5 5. Mineral nil 98.5

Chlorinated diphenyl containing about 50% chlorine Butyl naphthenate .5 6. Mineral 98.

Ortho dichlorbenzene .5 Hexadichlordiphenyl ether... .5 Methyl naphthenate ,5 '1. Mineral 08.75

Ortho dichlorbenzene .5 Hexachlor diphenyl ether .5 Chlorinated methyl naphthenate containing about chlorine .25

The "mineral oil" given in the foregoing list of compositions Nos. 1 to 7 inclusive, may be any suitable highly refined mineral lubricating oil having characteristics suiting the same for use as a crankcase lubricant. For example, the "mineral oil used in each of Examples 1 to 7 may be an S. A. E. 20 Pennsylvaniamotor oil having a viscosity index of about 100. As previously indicated, this "mineral oil may include, in addition to highly refined mineral lubricating oil, other constituents such as pour point depressors and the like. The S. A, E, number may, of course, vary in accordance with the usual standards which are observed in fitting an oil base to a particular use or condition of use.

11. Gear orils Per cent 8. Mineral oil 93 Chlorinated methyl cyclohexyl naphthenate containing about 40% chlo- 7 rine Per 9. Mineral oil I Chlorinated paraflin wax containing about 40% chlorine Methyl naphthenate 10. Mineral oil Chlorinated paraflin wax containin about 40% chlorine 1 8 Methyl naphthenate 1 Mineral oil 91.75 Chlorinated paraflin wax containing about. 40% chlorine Chlorinated methyl naphthenate containing about 20% chlorine Mineral oil Chlorinated paraflin wax containing about 40% chlorine Chlorbenzyl disulphide Methyl cyclohexyl naphthenate Mineral oil Chlorinated parailln wax containing about 40% chlorine Benzyl disulphide Chlorinated methyl naphthenate concent 92.5

- taining about 20% chlorine .1

14. Mineral oil Reaction product of chlorinated parafiin wax, containing about 35% chlorine, with sodium disulphide, such reaction product containing about 20% sulphur 10 Methyl naphthenate 1 an 8. A. E. 90 gear oil having a viscosity index.

of about 70. Here again, the mineral 011" component may include not only a refined mineral lubricating oil of properties such as those given above. but may also include other components such as thickening agents and the like.

Attention is directed particularly to Examples 12 to 15 above which are additionally characterized by the presence therein of an organic sulphur compound which, in certain instances, such as for example composition No. 12, may contain chlorine in the same molecule with the sulphur. This combination, 1. e., the combination oi an ester 0! a naphthenic acid with an organic sulphur compound, and with or without a separate organic halogen compound, has been found to be of particular utility. The organic sulphur compound and the esters of naphthenic acid, whether halogenated or unhalogenated. cooperate in the production 01 a final lubricating composition characterized by propertiessuch as oiliness, film strength, and ability to reduce wear,'which it is not possible to achieve with the use of eitherot these components alone, and which is more than 13 the cumulative efiect of such components when used separately.

Other modes of applying the principle of my invention may be employed instead of the one explained, change being made as regards the materials employed, provided the ingredients stated by any of the following claims or the equivalent of such stated ingredients be employed.

I, therefore, particularly point out and distinctly claim as my invention: 1

1. A lubricating composition comprising the combination of an ester of a naphthenic acid and an organic sulphur compound.

2. A lubricating composition comprising a hydrocarbon oil and minor amounts of both an ester of naphthenic acid and a separate organic compound containing an element of the class consisting of halogen and sulphur.

3. A lubricating composition comprising the combination of an ester of a naphthenic acid and an organic halogen compound having a' vapor pressure less than atmospheric at 140 C.

4. A lubricating composition comprising a hystable oil-soluble halogenated organic compound,

said compound having a vapor pressure less than 14 atmospheric at 140 C., and present in an amount less than 10% based on the amount of mineral oil but sumcient to provide a lubricating composition efiective to prevent seizure and scoring of 5 relatively moving metallic surfaces under pressure substantially in excess of 10,000 pounds per square inch.

7. A lubricating composition comprising the combination of an ester'ot a naphthenic acid and 10 a chlor benzyl sulphide.

8. A lubricating composition comprising the combination of methyl naphthenate and a chlor benzyl sulphide.

CARL F. PRUTION.

REFERENCES CITED The following references are of record in the file of this patent: i

OTHER REFERENCES Industrial and Engineering Chemistry, vol. 28,

#10, Oct. 1936.

35 Article by Lincoln et al., pages 1191-1197.

3 (Copy in Div. 64.) 252-58. 

